Finally tonight, her ohhism on the battle fun and father and son determined to make sure everyone knows about it. ABC's journalist had put together a documentary making sure our troops have someone telling their story. Reporter: Two years covering the frontlines of America's longest war. My son Carlos and I had one mission. To tell their story in our new film documents their determination. I looked at the eyes of the medics. They weren't going to let him die. Reporter: And absolute her rowism. Like the medic who on a March day in 2011 ran into a wall of gunfire to save his wounded buddies and an Afghan soldier. And before he died -- When he was bleeding out, he apologized for dying. Reporter: Five more soldiers in the 101st air Borns battalion would die that day. One of the deadliest in the war. After the cost of their sacrifice hit home. Especially for sergeant major Chris fields who waited until his men had left to let the tears of this entire war come out. Chris fields is now home. For him, like so many, the road between war and peace difficult to travel. There's not a moment that goes by that -- the remembrance of that. I knew them. Reporter: So much sacrifice. Mike Boettcher, ABC news.

This transcript has been automatically generated and may not be 100% accurate.

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